Lung cancer in women

Lung cancer is the leading cause of cancer death among women in the UK. It kills more women each year than breast cancer.

In 2008, more than 17,900 women were diagnosed with lung cancer in the UK, making it the third most common cancer in women after breast cancer and bowel cancer.

Lung cancer is declining among men, but the rate among women remains high. Between 1993 and 2008, cases of lung cancer in men fell by almost a third, while cases in women increased by 11%.

In the 1950s, for every case of lung cancer in women, there were six in men. That ratio is now three cases in women for every four in men, according to Cancer Research UK.

Women smoke more than men

The difference is due to smoking. Over the past few decades, men have increasingly quit smoking and their risk of lung cancer has dropped accordingly.

But women haven’t given up smoking at the same rates as men. In fact, more young women smoke now than young men. One study found that there has been a 5% increase in smoking since 1992 among women aged 16-25.

Young girls, especially, are increasingly taking up the habit.

One in four 16-year-old girls smokes compared with one in five boys of the same age. And 16% of 15-year-old girls are regular smokers compared to 14% of boys.

The number of under-16 girl smokers increased from 28% in 1992 to 37% in 2009. Among men, this proportion remained at around 40% over the same period, according to Cancer Research UK statistics.

Smoking is only part of the story, however. A high proportion of lung cancers in women occur in those who have never smoked (about one in six). There are other important differences between the sexes that make women more vulnerable than men.

Women’s lungs are more vulnerable

Several studies have indicated that women are more susceptible to developing lung cancer than men. Female smokers are twice as likely to develop lung cancer than male smokers, even when they smoke fewer cigarettes over a shorter period of time. Even among non-smokers, the risk of developing lung cancer is higher among women than men.

The reason isn’t clear, but it could be genetic. Scientists have discovered that a gene that speeds up lung cancer growth is more active in women. Studies have also suggested that the female hormone, oestrogen, may play a part in the development of lung cancer among women.

Women are more addicted to smoking

Women tend to find it harder to give up smoking than men. They have a higher rate of relapse and are much less likely to succeed using nicotine replacement products such as gum.

Scientists think this is because women are less physically dependent on nicotine than men but more behaviourally addicted, which is a more difficult type of addiction to kick.

A useful fact for women trying to give up smoking is that you’re twice as likely to succeed if you stop in the second half of your menstrual cycle. The high levels of the hormone progesterone in your bloodstream at this point in your cycle can help to move nicotine out of your system more quickly, therefore reducing withdrawal symptoms.

The good news

It’s not all bad news for women. On the positive side:

Evidence suggests that when women quit smoking, their lungs recover more quickly than men's.